First, organism sharing is currently working just fine. So I don't know what you mean by bringing it back, since it's here already and never left.
Second, what you're suggesting isn't sharing organisms, it's placing them in a dynamic league that gets auto-run. Which would certainly be a fun thing to play with, but...
What you're suggesting is impossible with FTP. It would require TCP/IP, and a server. We don't have a server, and one would cost at least something like $50 a month. Or require someone with a static IP to connect their computer directly to the internet, instead of through a firewall, and be sure to keep it running all the time.
So in the end, it's just not practical.